package com.nowcoder.entity;

import lombok.Data;

/**
 * 封装分页相关的信息
 * @author by lvshh
 * @version 1.0
 * @date 2020/4/21 18:14
 */

public class Page {
    //当前的页面
    private int current = 1;
    //显示上限
    private int limit = 10;
    //数据总数（用于计算总页数）
    private int rows;
    //查询路径(用来复用分页连接)
    private String path;

    public int getCurrent() {
        return current;
    }

    public void setCurrent(int current) {
        if(current >= 1){
            this.current = current;
        }
    }

    public int getLimit() {
        return limit;
    }

    public void setLimit(int limit) {
        if (limit >=1 && limit <=100){
            this.limit = limit;
        }
    }

    public int getRows() {
        return rows;
    }

    public void setRows(int rows) {
        if (rows >= 0){
            this.rows = rows;
        }
    }

    public String getPath() {
        return path;
    }

    public void setPath(String path) {
        this.path = path;
    }

    /**
     * 获取当前页的起始行
     */
    public int getOffset(){
        return (current -1) * limit;
    }

    /**
     * 获取总页数
     * @return
     */
    public int getTotal(){
        // rows/limit[+1]
        if(rows % limit == 0){
            return rows/limit;
        }else {
            return rows/limit +1 ;
        }
    }

    /**
     * 获取起始页码
     * @return
     */
    public int getFrom(){
        int from = current - 2;
        return from < 1 ? 1 : from;
    }

    /**
     * 获取结束页码
     * @return
     */
    public int getTo(){
        int to = current + 2;
        int total = getTotal();
        return to > total ? total : to;
    }
}
